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9.8
CRITICAL CVSS 3.1
CVE-2021-33391
"HTACG HTML Tidy Command Injection Vulnerability"
Description

An issue in HTACG HTML Tidy v5.7.28 allows attacker to execute arbitrary code via the -g option of the CleanNode() function in gdoc.c.

INFO

Published Date :

Feb. 17, 2023, 6:15 p.m.

Last Modified :

March 18, 2025, 7:15 p.m.

Remotely Exploit :

Yes !

Source :

[email protected]
Affected Products

The following products are affected by CVE-2021-33391 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
1 Htacg tidy
: Total Affected Vendor : 2 | Products : 2
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL [email protected]
CVSS 3.1 CRITICAL 134c704f-9b21-4f2e-91b3-4a467353bcc0
Solution
The HTML Tidy library is vulnerable to command injection.
  • Update the affected libtidy-dev, libtidy5deb1, and/or tidy packages.
  • If updating is not possible, consider removing the affected packages if they are not essential.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-33391.

URL Resource
https://github.com/htacg/tidy-html5/issues/946 Exploit Patch
https://github.com/htacg/tidy-html5/issues/946 Exploit Patch
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-33391 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-33391 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-33391 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2021-33391 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Mar. 18, 2025

    Action Type Old Value New Value
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Added CWE CWE-416
  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://github.com/htacg/tidy-html5/issues/946
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    Feb. 28, 2023

    Action Type Old Value New Value
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://github.com/htacg/tidy-html5/issues/946 No Types Assigned https://github.com/htacg/tidy-html5/issues/946 Exploit, Patch
    Added CWE NIST CWE-416
    Added CPE Configuration AND OR *cpe:2.3:a:htacg:tidy:5.7.28:*:*:*:*:*:*:* OR cpe:2.3:o:linux:linux_kernel:-:*:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 9.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.22 }} -0.01%

score

0.44523

percentile